Cranioclast wrote:Or maybe I am picky. I'm not sure if I'm ever going to get comfortable with the twitchiness of the Tiger's fueling at small throttle openings. Everything else about the bike is perfect for me, but I get these annoying lurches when trying to maintain a speed below 25 mph (especially on bumpy roads) and engine braking can come on abruptly if I don't roll off ever so smoothly.

And this is where you install either an aftermarket, emissions-violating ECU, an emissions-violating ECU reflash, or something that violates emissions laws, and smooth that shit out.

Alternately, look into TPS (throttle position sensor) calibration. A miscalibrated TPS will cause this too.

The F800GS is the same. You can do 30 in 1st easily without even hitting 5000 RPM but 0-15 is kinda twitchy. I'm told a power commander helps, and that due to emissions laws here compared to say Germany the bike is a little anemic in comparison. A lot of people remove a charcoal canister of some sort.

I think an after market exhaust, PC+ custom tuning map or an AutoTune module are in my future, but it's not a rush. The FZ6 I thought was bad but it's manageable.

shannim wrote:

Incidentally the ride leader told me that my Tourmaster made me VERY visible in her rear view mirror, and since I ride sweep 99% of the time she knew that when she saw me everybody was ok. So while the visibility yellow should not be counted on, it certainly can't hurt your visibility. I think my next touring helmet will be white.

Sucks about your friend. I hope he gets well and gets back on the saddle soon.

Regarding white helmets, they are great for visibility (though not guaranteed). Here's a video Cranioclast took of me last fall. My solid white helmet is very visible in my opinion.

As I'm sure you know there's a correlation between white helmeted riders and accidents, though it might be that safer riders prefer white helmets over white helmets making people more visible.

The question is, which is more visible, a white helmet, or a Fluorescent green helmet?

Edit: Just watched your video you're right the white helmet is very visible even at a distance. I used to like the black on black on black on a black bike look like my buddy does with his mfg-stickers removed jet black 'Strom, matte black Shoei helmet and black Triumph riding suit, but now I like whatever adds to my chances of getting home ok.

Or maybe I am picky. I'm not sure if I'm ever going to get comfortable with the twitchiness of the Tiger's fueling at small throttle openings. Everything else about the bike is perfect for me, but I get these annoying lurches when trying to maintain a speed below 25 mph (especially on bumpy roads) and engine braking can come on abruptly if I don't roll off ever so smoothly.

And this is where you install either an aftermarket, emissions-violating ECU, an emissions-violating ECU reflash, or something that violates emissions laws, and smooth that shit out.

Alternately, look into TPS (throttle position sensor) calibration. A miscalibrated TPS will cause this too.

The thing is, the Triumph ECU is programmable. I have the receipt for when the TOR ("Triumph Off-Road") exhaust was installed and it shows that they updated to the latest TOR tune, which is still the most current one. So, in theory, I've already got the "race" exhaust and tune. There are people who have had success at minimizing the "snatch" with custom tunes, but they've all removed the catalytic converter and opened up the air box as well. The idea is that the motor is basically the Speed Triple motor, but with more restrictive intake and exhaust, and since the Speed Triple doesn't have the "snatch," then opening up the Tiger to Speed Triple specs and replicating the tune will fix it. It's an option, I guess. Though I'm not looking for more power and I don't want to increase noise, emissions or fuel consumption, so I'd rather keep it as stock as possible. The Sprint and Speed Triple manage to meet emissions requirements without the problem, so it doesn't seem like you need to go that route.

I haven't seen the TPS mentioned with regard to this problem, but some people claim to have improved it by taking slack out of the throttle cable. I'll check both and see if there's anything there.

It's really not that bad and there's a good chance I'll adapt and come to work around it. It just doesn't seem right and I'm compelled to fix it. Every time the bike gets upset because I move the throttle 1mm when I hit a bump mid-corner, it's going to piss me off. It's not going to make me crash, it's just going to piss me off if I haven't been able to fix it.

Or maybe I am picky. I'm not sure if I'm ever going to get comfortable with the twitchiness of the Tiger's fueling at small throttle openings. Everything else about the bike is perfect for me, but I get these annoying lurches when trying to maintain a speed below 25 mph (especially on bumpy roads) and engine braking can come on abruptly if I don't roll off ever so smoothly.

And this is where you install either an aftermarket, emissions-violating ECU, an emissions-violating ECU reflash, or something that violates emissions laws, and smooth that shit out.

Alternately, look into TPS (throttle position sensor) calibration. A miscalibrated TPS will cause this too.

The thing is, the Triumph ECU is programmable. I have the receipt for when the TOR ("Triumph Off-Road") exhaust was installed and it shows that they updated to the latest TOR tune, which is still the most current one. So, in theory, I've already got the "race" exhaust and tune. There are people who have had success at minimizing the "snatch" with custom tunes, but they've all removed the catalytic converter and opened up the air box as well. The idea is that the motor is basically the Speed Triple motor, but with more restrictive intake and exhaust, and since the Speed Triple doesn't have the "snatch," then opening up the Tiger to Speed Triple specs and replicating the tune will fix it. It's an option, I guess. Though I'm not looking for more power and I don't want to increase noise, emissions or fuel consumption, so I'd rather keep it as stock as possible. The Sprint and Speed Triple manage to meet emissions requirements without the problem, so it doesn't seem like you need to go that route.

I haven't seen the TPS mentioned with regard to this problem, but some people claim to have improved it by taking slack out of the throttle cable. I'll check both and see if there's anything there.

It's really not that bad and there's a good chance I'll adapt and come to work around it. It just doesn't seem right and I'm compelled to fix it. Every time the bike gets upset because I move the throttle 1mm when I hit a bump mid-corner, it's going to piss me off. It's not going to make me crash, it's just going to piss me off if I haven't been able to fix it.

Ironhide is pretty much pure stock right now and I've noticed it's a bit touchy in lower gears but nothing as what you are saying. Maybe it's coming from my Versys which is pretty touchy as well, or possibly I just lack finesse but it's been pretty good so far.

Or maybe I am picky. I'm not sure if I'm ever going to get comfortable with the twitchiness of the Tiger's fueling at small throttle openings. Everything else about the bike is perfect for me, but I get these annoying lurches when trying to maintain a speed below 25 mph (especially on bumpy roads) and engine braking can come on abruptly if I don't roll off ever so smoothly.

And this is where you install either an aftermarket, emissions-violating ECU, an emissions-violating ECU reflash, or something that violates emissions laws, and smooth that shit out.

Alternately, look into TPS (throttle position sensor) calibration. A miscalibrated TPS will cause this too.

The thing is, the Triumph ECU is programmable. I have the receipt for when the TOR ("Triumph Off-Road") exhaust was installed and it shows that they updated to the latest TOR tune, which is still the most current one. So, in theory, I've already got the "race" exhaust and tune. There are people who have had success at minimizing the "snatch" with custom tunes, but they've all removed the catalytic converter and opened up the air box as well. The idea is that the motor is basically the Speed Triple motor, but with more restrictive intake and exhaust, and since the Speed Triple doesn't have the "snatch," then opening up the Tiger to Speed Triple specs and replicating the tune will fix it. It's an option, I guess. Though I'm not looking for more power and I don't want to increase noise, emissions or fuel consumption, so I'd rather keep it as stock as possible. The Sprint and Speed Triple manage to meet emissions requirements without the problem, so it doesn't seem like you need to go that route.

I haven't seen the TPS mentioned with regard to this problem, but some people claim to have improved it by taking slack out of the throttle cable. I'll check both and see if there's anything there.

It's really not that bad and there's a good chance I'll adapt and come to work around it. It just doesn't seem right and I'm compelled to fix it. Every time the bike gets upset because I move the throttle 1mm when I hit a bump mid-corner, it's going to piss me off. It's not going to make me crash, it's just going to piss me off if I haven't been able to fix it.

Opening up the intake/exhaust makes an engine *more* prone to jerky low-rpm behavior, not less. This holds true across all piston engines; it's just the nature of the beast. It's got to be a fueling issue.

If you've got the race exhaust and ECU tune and it's still snatchy, I'd see if you could get your shop to try the Arrow tune, as it is more aggressively fueled. Every shop is different, but I would hope that they'd let you try it without additional $ on your part to see if it clears up the issue. I know I would have, if a customer came to me with the problem you're describing.

Silly question. I'm planning on getting a newer bike within the next couple years(hopefully a wee or a versys!), but I probably won't have much time to ride until then being away at college and such. Does it make sense to keep my beater YZF600R around as a track day / general fun kind of bike? The most I could sell it for is probably around $1500

My general feeling is that unless you're going to be regularly riding a bike, the best choice is to sell it. Even just sitting doing nothing, everything on a motorcycle ages, and registration & insurance fees never stop.

Now, if you want a track bike, and plan on spending regular amounts of time running laps, great! If it's something you think you'd like to try, but don't have the time/money to do it regularly, maybe not so great, and you'd be better-served by selling the bike you aren't using while you can still recover some value from it.

And this is where you install either an aftermarket, emissions-violating ECU, an emissions-violating ECU reflash, or something that violates emissions laws, and smooth that shit out.

Alternately, look into TPS (throttle position sensor) calibration. A miscalibrated TPS will cause this too.

Both of these can be done at home with the free TuneECU software, any Windows laptop (I use a cheap netbook), and a $20 USB/OBD-II cable.

The one awesome thing about Triumph is that they allow at-home programming of the ECU.

Edit: And derp, should have read the rest of the thread. You already know about the retuning. Still, it might be worth tweaking at home, since it costs all of $20 for the cable if you don't know anybody with one.

My general feeling is that unless you're going to be regularly riding a bike, the best choice is to sell it. Even just sitting doing nothing, everything on a motorcycle ages, and registration & insurance fees never stop.

Now, if you want a track bike, and plan on spending regular amounts of time running laps, great! If it's something you think you'd like to try, but don't have the time/money to do it regularly, maybe not so great, and you'd be better-served by selling the bike you aren't using while you can still recover some value from it.

I agree with this. If you're going to somehow ride it, keep it. But if you really aren't going to ride it, sell it. The worst thing you can possibly do to a motorcycle short of crashing it is to let it sit.

Opening up the intake/exhaust makes an engine *more* prone to jerky low-rpm behavior, not less. This holds true across all piston engines; it's just the nature of the beast. It's got to be a fueling issue.

If you've got the race exhaust and ECU tune and it's still snatchy, I'd see if you could get your shop to try the Arrow tune, as it is more aggressively fueled. Every shop is different, but I would hope that they'd let you try it without additional $ on your part to see if it clears up the issue. I know I would have, if a customer came to me with the problem you're describing.

Thanks. I wouldn't say it's just a low-RPM thing, though. If it was, I could probably just use more clutch to deal with it. Where it bothers me is when trying to roll off the throttle just a little bit while cruising anywhere up to 6K or so. Distinct acceleration and deceleration aren't that much of a problem. It's just the fine control. I think. I'll take a long ride this week and try to come up with a more complete description.

I need to borrow a laptop and get TuneECU on it so I can see what's actually installed. It's totally possible that the dealer who installed the exhaust never actually did anything and it still has the same tune it left the factory with five years ago. The closest Triumph dealer is a couple hours away, so it probably makes sense to deal with it myself.

Funny observation: At one point, it looks like people on Tiger1050.com were replacing the throttle tube with the one from the Sprint and claiming it cured the problem. Then someone pointed out that they were the same part number. Doh!

Still, it might be worth tweaking at home, since it costs all of $20 for the cable if you don't know anybody with one.

I actually have the cable. I just don't own a laptop anymore. I wasn't really thinking about that when I ordered the cable. I could drag my iMac out to the garage, but it just doesn't sound appealing. I'm sure I know someone with an old Windows laptop lying around. I just have to ask.

Speaking of torque/power curves (I'm jealous of how smooth Saint's F800GS's curves look), I found this comparison of stock versus an Akrapovic exhaust online for the FZ6. As you can see, the stock torque curve has peaks and valleys all over the place. There's also a flat spot in power at 8000 RPM. A Power Commander or JuiceBox would smooth this stuff out, right?

Speaking of torque/power curves (I'm jealous of how smooth Saint's F800GS's curves look), I found this comparison of stock versus an Akrapovic exhaust online for the FZ6. As you can see, the stock torque curve has peaks and valleys all over the place. There's also a flat spot in power at 8000 RPM. A Power Commander or JuiceBox would smooth this stuff out, right?

Apparently yes. But I eventually got used to the twitchy first gear and flat spots. But I have no doubt you'd enjoy it more with a PC...eventually. Ride it stock first and then decide. I'd like to get one even for the F800GS once I ride it a few thousand more miles. Incidentally does installing a PC void your warranty in any way?

Today the rains returned and I felt it was important to ride again in the rain to get over my fear since last time we all know what happened. I took the BMW with ABS and had zero issues. I just took it slow and easy on the city streets, avoided painted ground, and on the highway I stuck to one lane over from the passing lane and rode at traffic speeds, ~ 60 MPH. I didn't re-Rain-X my visor but otherwise, no issues. Stayed dry too in the Tourmaster jacket and pants.

If you want a tabletop dyno chart, just look at the 1050 motor, it's something like a 6 ft/lb variance between 3000rpm & peak torque @ almost 7k if I remember right.

There are amusing things about steep power curves as well though, highly entertaining, if not potentially dangerous. I actually really miss the manic power surge ~8k on the hayabusa, the triumph just doesn't have the exiting rush of a 1L+ 4cylinder.

With regards to the snatchy tiger issue, which tune are you running? have you tried just running a speed triple tune? There are a variety available with various aftermarket intake/exhaust options (or stock intake, aftermarket high exhaust, gp, etc) with & without cat that are at least decently close. Mine is modified a bit because with as lean as the ecu likes to run the bike, the timing is maybe a bit too aggressive for my tastes.

Torque is a measure of the turning force on an object such as a wheel, right, while HP is a measure of "power". I know someone posted a formula for it, but doesn't really mean anything to me. Can an engine have a lot of torque but lower top power? Can an engine have a lot of top power but little torque? How can something have a lot of "HP" but no ability to turn the wheel?

If we post the F800GS again:

The Tiger has more Torque and HP but I get the same torque at higher RPMs... but the drop off from 3400 from the Tiger is small. You can also see past 8000 the power dies but it just keeps climbing on the Tiger.

Torque is twisting force, as you said. Horsepower is total power output. The two are related, but not the same. Think of horsepower as torque multiplied by how fast the engine is producing it.

Horsepower is a direct function of torque and rpm. If you have an engine putting out a large torque number at high rpm, it will be producing a lot of power. If an engine has low torque at high rpm, it will produce less power, but it is still possible to produce significant power, *if* the drop in torque is less than the boost in power given by the increase in RPM.

(This is how gas turbines work, by the way. They do not produce very much torque, but they spin at tremendously high RPM, and thus produce a lot of power in a small package.)

Think of shifting gears while riding a bicycle. If you're in a tall gear, it takes a lot of effort (torque) to pedal, and if you're in a short gear, it takes very little effort at all. The reason being that to travel the same distance in a short gear requires many more turns of the pedal. In the tall gear case, you're producing a lot of torque at low RPM, and in the short gear case, you're producing very little torque at a higher RPM.

Extending that analogy, I'm sure you can picture that if you were producing a lot of torque at high RPM, you'd be hauling ass, and low torque/low rpm would equal to just puttering around. Same way with engines.

Torque is twisting force, as you said. Horsepower is total power output. The two are related, but not the same. Think of horsepower as torque multiplied by how fast the engine is producing it.

Horsepower is a direct function of torque and rpm. If you have an engine putting out a large torque number at high rpm, it will be producing a lot of power. If an engine has low torque at high rpm, it will produce less power, but it is still possible to produce significant power, *if* the drop in torque is less than the boost in power given by the increase in RPM.

(This is how gas turbines work, by the way. They do not produce very much torque, but they spin at tremendously high RPM, and thus produce a lot of power in a small package.)

I sort of get it. Is this a good example? On the FZ6, sub 5500 RPM the engine was producing plenty of "HP", but it wasn't translating it well into the torque...on the F800GS, the engine at 5500 RPM is producing HP which is clearly being translated into power to the wheel, thus translating into a lot of "torque"?

Pont wrote:

Quote:

How can something have a lot of "HP" but no ability to turn the wheel?

Think of it like leverage.

An 80lb old woman using a 3' long wrench to turn a hard-stuck bolt? Lots of torque, low HP.

A 300lb body builder using a 3" wrench to try and turn a hard-stuck bolt? No torque, lots of HP.

Torque is twisting force, as you said. Horsepower is total power output. The two are related, but not the same. Think of horsepower as torque multiplied by how fast the engine is producing it.

Horsepower is a direct function of torque and rpm. If you have an engine putting out a large torque number at high rpm, it will be producing a lot of power. If an engine has low torque at high rpm, it will produce less power, but it is still possible to produce significant power, *if* the drop in torque is less than the boost in power given by the increase in RPM.

(This is how gas turbines work, by the way. They do not produce very much torque, but they spin at tremendously high RPM, and thus produce a lot of power in a small package.)

I sort of get it. Is this a good example? On the FZ6, sub 5500 RPM the engine was producing plenty of "HP", but it wasn't translating it well into the torque...on the F800GS, the engine at 5500 RPM is producing HP which is clearly being translated into power to the wheel, thus translating into a lot of "torque"?

Pont wrote:

Quote:

How can something have a lot of "HP" but no ability to turn the wheel?

Think of it like leverage.

An 80lb old woman using a 3' long wrench to turn a hard-stuck bolt? Lots of torque, low HP.

A 300lb body builder using a 3" wrench to try and turn a hard-stuck bolt? No torque, lots of HP.

This is a great analogy that I easily grasped.

Think of shifting gears while riding a bicycle. If you're in a tall gear, it takes a lot of effort (torque) to pedal, and if you're in a short gear, it takes very little effort at all. The reason being that to travel the same distance in a short gear requires many more turns of the pedal. In the tall gear case, you're producing a lot of torque at low RPM, and in the short gear case, you're producing very little torque at a higher RPM.

Invert your thinking. Horsepower is not translating in to torque. Torque, multiplied by engine RPM, is what translates into horsepower.

Invert your thinking. Horsepower is not translating in to torque. Torque, multiplied by engine RPM, is what translates into horsepower.

So Torque is the power actually being produced by the engine, and horsepower is how well it can apply the torque to the road?

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To my un-educated mind, when I ride the FZ6 at too low an RPM, it's rotating thousands of times per minute, but not much movement is going on. When I increase the RPM past a certain point, I get "pull". In the Inline-4 I can keep increasing the RPM for a very long time and make power. If I shift gears, I lose the "pull" until the RPM climbs back into the power band.

On the F800, it seems to "pull" at any RPM...when I shift, the RPMs don't drop that much, but then again when I rev they don't jump that much either.

I feel I instinctively feel the difference between a torquey and non-torquey bike but for the life of me can't explain it.

Torque is a measure of the turning force on an object such as a wheel, right, while HP is a measure of "power". I know someone posted a formula for it, but doesn't really mean anything to me. Can an engine have a lot of torque but lower top power? Can an engine have a lot of top power but little torque? How can something have a lot of "HP" but no ability to turn the wheel?

Horsepower = Torque * RPM

That's not exactly the formula (there are coefficients in there) but it's the right general idea.

- How can something have a lot of HP but no ability to turn the wheel? With *no* ability to turn the wheel, it can't make high hp. But with just a little ability to turn the wheel, it can make lots of horsepower if the engine can rev high enough. For example a motor that puts out 1 ft-lb of torque could achieve 100hp if it could spin at 525,200rpm. For reference, 1 ft-lb of torque is less than you apply when finger-tightening a bolt.

Invert your thinking. Horsepower is not translating in to torque. Torque, multiplied by engine RPM, is what translates into horsepower.

So Torque is the power actually being produced by the engine, and horsepower is how well it can apply the torque to the road?

Close! Torque is how much twisting power an engine has, and horsepower is how much of that twisting power in can put to the ground over a unit of time. Like if you are pedaling a bike at 50 RPM, and then at 100 RPM. Even if the amount of twisting force is the same, you're producing more power pedaling at the higher rate.

Torque is a measure of the turning force on an object such as a wheel, right, while HP is a measure of "power". I know someone posted a formula for it, but doesn't really mean anything to me. Can an engine have a lot of torque but lower top power? Can an engine have a lot of top power but little torque? How can something have a lot of "HP" but no ability to turn the wheel?

Horsepower = Torque * RPM

That's not exactly the formula (there are coefficients in there) but it's the right general idea.

- How can something have a lot of HP but no ability to turn the wheel? With *no* ability to turn the wheel, it can't make high hp. But with just a little ability to turn the wheel, it can make lots of horsepower if the engine can rev high enough. For example a motor that puts out 1 ft-lb of torque could achieve 100hp if it could spin at 525,200rpm. For reference, 1 ft-lb of torque is less than you apply when finger-tightening a bolt.

Ok this makes the most sense to me so far. Sorry for the thread-derail but I'm learning a TON from this.

I sort of get it. Is this a good example? On the FZ6, sub 5500 RPM the engine was producing plenty of "HP", but it wasn't translating it well into the torque...on the F800GS, the engine at 5500 RPM is producing HP which is clearly being translated into power to the wheel, thus translating into a lot of "torque"?

You're misunderstanding what hp feels like. Horsepower = top speed. Period. At 5500 RPM the engine was producing exactly as much HP as you needed to maintain whatever speed you were doing at whatever speed you were in.

Torque on the other hand is what feels like the bike wants to wheelie, or rip the bars out of your hands (depending on the bike's geometry and center of gravity). Roll on the throttle and not much happens? Not a lot of torque being applied to the rear wheel.

Saint wrote:

This is a great analogy that I easily grasped.

Except that it's totally wrong because there's no concept of RPM. It's a great analogy for the relationship of engine power to gearing, but has nothing to do with the relationship of hp and torque.

How fast the components can move without running into each other. Or the rev limiter, whichever comes first.

In practice, the ability to move the valves up and down in time with the pistons going up and down tends to be the limiting factor, at least in sport bikes. When the valve can't move out of the way of the piston, the two collide with disastrous results. That's why the 2011 ZX-10R was recalled--the valve springs allowed the valves to float (the spring didn't pull them back before the cam pushed them back down again), and they could impact the pistons.

Torque on the other hand is what feels like the bike wants to wheelie, or rip the bars out of your hands (depending on the bike's geometry and center of gravity). Roll on the throttle and not much happens? Not a lot of torque being applied to the rear wheel.

This is what the BMW feels like. Also the Super Tenere when I rode it. Not so much the FZ6.

So on Top Gear they're always talking about Horsepower of the cars, but occasionally they mention some crazy Mercedes "Black" edition production 700-1000 "torques", but it can't seem to put it down without losing traction.

So a 500 HP car is just a car with a higher top speed than a 450 HP car, but the 450 HP car could have more "torque" theoretically?

This is what the BMW feels like. Also the Super Tenere when I rode it. Not so much the FZ6.

Yep. Because the F800GS and Super Tenere are large displacement twins. Your FZ6 is an inline 4. The former have lots of torque, not so much (relative) hp because of big heavy pistons that take a lot of energy to move up and down, so they can't go up and down as fast. But lots of bang per cylinder firing because they're just plain bigger cylinders that can hold more fuel and more air.

Saint wrote:

So on Top Gear they're always talking about Horsepower of the cars, but occasionally they mention some crazy Mercedes "Black" edition production 700-1000 "torques", but it can't seem to put it down without losing traction.

So a 500 HP car is just a car with a higher top speed than a 450 HP car, but the 450 HP car could have more "torque" theoretically?

Yep. HP alone tells you nothing about torque. Torque can tell you something about how the car will feel to drive, but tells you nothing about top speed unless you know the rev limit. A car that puts out 1000 ft-lbs of torque, I can see why you can never apply it. There are no tires sticky enough to retain traction. Think about yanking the tablecloth out from under the wineglass--same concept. That engine could spin up the wheels so fast there's not a prayer of moving the car before the tires slip.

And to add to the fun of your 450HP car vs. 500HP car, you also need to consider the power-to-weight ratio. A 500HP car is quick. A 500HP bike is ungodly fast. The key is that the bike weighs maybe 1/8 what the car weighs. It takes way less power to accelerate the bike, but they both have the same power available, so the bike goes way faster. On a smaller scale, this is why a 100hp ZX6R is way faster than a 100hp Harley.

And to add to the fun of your 450HP car vs. 500HP car, you also need to consider the power-to-weight ratio. A 500HP car is quick. A 500HP bike is ungodly fast. The key is that the bike weighs maybe 1/8 what the car weighs. It takes way less power to accelerate the bike, but they both have the same power available, so the bike goes way faster.

I learned that last bit playing Gran Turismo.

This part I learned on my own. They do harp on Power-to-weight ratios all the time on TG, which is why the Arial Atom and Caterham Seven Superlight R500 can kick the Veyron's ass on the track.

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Here's another question: When riding the twisty's this weekend, for the first time ever, cars needed to yield to my "faster traffic" at turnouts (vs. the opposite when I was learning. For once cars I passed became distant specs in my rear view mirrors after about 30 seconds. We were often doubling the speed limit (doing 70 in 35 zones), and taking turns faster than cars typically could.

Yet, when they raced a BMW S1000RR vs. the Arial Atom, the Atom won, and James May said "He can't put the power down in the corners like I can". Now, the Atom is not a typical car, but if you had a bike and a car with similar power-to-weight ratios, which would have the advantage on a track?

So the typical motorcycle, having a great power to weight ratio than the typical car, will typically win in the corners (and even straights)? Once you factor in a "sports car" which has a far better power to weight ratio you might start to see the car win?

Cars will win in the corners every time, as the limiting factor in corners is grip, not power. Motorcycles will win on the straightaways, *if* they have the superior power/weight ratio. If both car & bike have the same power/weight, the motorcycle will get utterly demolished, as the drag coefficient for bikes is awful.

Of course, it is very difficult to get a car to put out enough power to compete on power/weight. An R1 + rider has a power:weight ratio of 1hp:4#. Even a high-end sports car, like a Porsche 911 Turbo, has a power:weight ratio of 1hp:8#.

I saw F1 cars race at Indianapolis for eight years and then MotoGP bikes for four. I've sat in the same corners and seen the fastest bikes and fastest cars in the world race on the same bit of track (granted, going in different directions) and there's just no contest. While the bikes flow elegantly through a series of corners, the F1 cars just explode through them. They brake later and accelerate earlier and change direction faster, despite having fewer electronic aides than the MotoGP bikes. I love watching the MotoGP riders because I know how amazingly talented they are, but if you really want to see something get around a track fast, you want to see an F1 car do it.

Okay, I didn't read all of that, so I apologize if this has already been stated.

Here's my simplified explanation.

Torque is a measure of the force applied to the ground through the wheel (angular force). It is directly proportional to acceleration (accelerating the mass of the bike through the application of angular force). Torque is what makes you accelerate fast (having a quick bike).

Horsepower is a measure of the rate at which energy is transformed into work and is thus related to maintaining your momentum (mass times speed). So horsepower is what makes you go fast.

Torque is how much twisting power an engine has, and horsepower is how much of that twisting power in can put to the ground over a unit of time. Like if you are pedaling a bike at 50 RPM, and then at 100 RPM. Even if the amount of twisting force is the same, you're producing more power pedaling at the higher rate.

This is the clearest description I think I've seen. Read that a couple times. Think about it. Act it out if necessary. It should make sense.

Torque is how much twisting power an engine has, and horsepower is how much of that twisting power in can put to the ground over a unit of time. Like if you are pedaling a bike at 50 RPM, and then at 100 RPM. Even if the amount of twisting force is the same, you're producing more power pedaling at the higher rate.

This is the clearest description I think I've seen. Read that a couple times. Think about it. Act it out if necessary. It should make sense.

But technically that's not correct (it's close). Torque is a measure of rotational force (accelerating a mass), not power. It's a twisting force, not a twisting power.

Power is defined as the rate at which work is performed or energy is converted. So the more horsepower, the more energy is being converted to perform work for a given amount of time. More work means more faster top speed.